us president barack obama said tuesday he believed pakistan was making progress in fighting extremism as he tried to assuage india 's concerns about its historic rival .

A summary about the text above: obama sees pakistan progress on extremism

chinese researchers have found that a robust antibody against the sars coronavirus remained in the bodies of recovered sars patients for more than three years .

A summary about the text above: long-term persistence of antibody found in recovered sars patients

american troops in saudi arabia have been put on the highest possible state of alert because of `` concrete '' reports that terrorists may be planning another attack on military installations there , the defense department said on thursday .

A summary about the text above: u.s. troops on heightened alert in saudi arabia

as investigators struggled to determine who was behind the attacks on israeli targets here on thursday , they are re-examining evidence that east africa has served as both a useful base and a target for osama bin laden 's terror network for nearly a decade .

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after blast kenya reviews al-qaida 's trail in east africa